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-rw-r--r--src/data/hashmap.rs137
1 files changed, 0 insertions, 137 deletions
diff --git a/src/data/hashmap.rs b/src/data/hashmap.rs
deleted file mode 100644
index d2ea980..0000000
--- a/src/data/hashmap.rs
+++ /dev/null
@@ -1,137 +0,0 @@
-//! A hash-map that behaves deterministically when the
-//! `enhanced-determinism` feature is enabled.
-
-#[cfg(all(feature = "enhanced-determinism", feature = "serde-serialize"))]
-use indexmap::IndexMap as StdHashMap;
-#[cfg(all(not(feature = "enhanced-determinism"), feature = "serde-serialize"))]
-use std::collections::HashMap as StdHashMap;
-
-/// Serializes only the capacity of a hash-map instead of its actual content.
-#[cfg(feature = "serde-serialize")]
-pub fn serialize_hashmap_capacity<S: serde::Serializer, K, V, H: std::hash::BuildHasher>(
- map: &StdHashMap<K, V, H>,
- s: S,
-) -> Result<S::Ok, S::Error> {
- s.serialize_u64(map.capacity() as u64)
-}
-
-/// Creates a new hash-map with its capacity deserialized from `d`.
-#[cfg(feature = "serde-serialize")]
-pub fn deserialize_hashmap_capacity<
- 'de,
- D: serde::Deserializer<'de>,
- K,
- V,
- H: std::hash::BuildHasher + Default,
->(
- d: D,
-) -> Result<StdHashMap<K, V, H>, D::Error> {
- struct CapacityVisitor;
- impl<'de> serde::de::Visitor<'de> for CapacityVisitor {
- type Value = u64;
-
- fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
- write!(formatter, "an integer between 0 and 2^64")
- }
-
- fn visit_u64<E: serde::de::Error>(self, val: u64) -> Result<Self::Value, E> {
- Ok(val)
- }
- }
-
- let capacity = d.deserialize_u64(CapacityVisitor)? as usize;
- Ok(StdHashMap::with_capacity_and_hasher(
- capacity,
- Default::default(),
- ))
-}
-
-/*
- * FxHasher taken from rustc_hash, except that it does not depend on the pointer size.
- */
-#[cfg(feature = "enhanced-determinism")]
-pub type FxHashMap32<K, V> = indexmap::IndexMap<K, V, std::hash::BuildHasherDefault<FxHasher32>>;
-#[cfg(feature = "enhanced-determinism")]
-pub use {self::FxHashMap32 as HashMap, indexmap::map::Entry};
-#[cfg(not(feature = "enhanced-determinism"))]
-pub use {rustc_hash::FxHashMap as HashMap, std::collections::hash_map::Entry};
-
-const K: u32 = 0x9e3779b9;
-
-// Same as FxHasher, but with the guarantee that the internal hash is
-// an u32 instead of something that depends on the platform.
-pub struct FxHasher32 {
- hash: u32,
-}
-
-impl Default for FxHasher32 {
- #[inline]
- fn default() -> FxHasher32 {
- FxHasher32 { hash: 0 }
- }
-}
-
-impl FxHasher32 {
- #[inline]
- fn add_to_hash(&mut self, i: u32) {
- use std::ops::BitXor;
- self.hash = self.hash.rotate_left(5).bitxor(i).wrapping_mul(K);
- }
-}
-
-impl std::hash::Hasher for FxHasher32 {
- #[inline]
- fn write(&mut self, mut bytes: &[u8]) {
- use std::convert::TryInto;
- let read_u32 = |bytes: &[u8]| u32::from_ne_bytes(bytes[..4].try_into().unwrap());
- let mut hash = FxHasher32 { hash: self.hash };
- assert!(std::mem::size_of::<u32>() <= 8);
- while bytes.len() >= std::mem::size_of::<u32>() {
- hash.add_to_hash(read_u32(bytes) as u32);
- bytes = &bytes[std::mem::size_of::<u32>()..];
- }
- if (std::mem::size_of::<u32>() > 4) && (bytes.len() >= 4) {
- hash.add_to_hash(u32::from_ne_bytes(bytes[..4].try_into().unwrap()) as u32);
- bytes = &bytes[4..];
- }
- if (std::mem::size_of::<u32>() > 2) && bytes.len() >= 2 {
- hash.add_to_hash(u16::from_ne_bytes(bytes[..2].try_into().unwrap()) as u32);
- bytes = &bytes[2..];
- }
- if (std::mem::size_of::<u32>() > 1) && bytes.len() >= 1 {
- hash.add_to_hash(bytes[0] as u32);
- }
- self.hash = hash.hash;
- }
-
- #[inline]
- fn write_u8(&mut self, i: u8) {
- self.add_to_hash(i as u32);
- }
-
- #[inline]
- fn write_u16(&mut self, i: u16) {
- self.add_to_hash(i as u32);
- }
-
- #[inline]
- fn write_u32(&mut self, i: u32) {
- self.add_to_hash(i as u32);
- }
-
- #[inline]
- fn write_u64(&mut self, i: u64) {
- self.add_to_hash(i as u32);
- self.add_to_hash((i >> 32) as u32);
- }
-
- #[inline]
- fn write_usize(&mut self, i: usize) {
- self.add_to_hash(i as u32);
- }
-
- #[inline]
- fn finish(&self) -> u64 {
- self.hash as u64
- }
-}